In recent years, relationships between reactive oxygen species and various diseases and aging have attracted attention. Examples of reactive oxygen species may include a superoxide anion, singlet oxygen (1O2), hydrogen peroxide (H2O2), and a hydroxyl radical (.OH). The reactive oxygen species have extremely high reactivity and are known to cause various problems.
Nucleic acids and proteins are oxidized by the reactive oxygen species. In particular, lipids are more sensitive to oxidation than nucleic acids and proteins. Of the reactive oxygen species, a hydroperoxyl radical (hereinafter referred to radicals) is produced by oxidation of lipids constituting a cell membrane. Lipid peroxidation is an addition reaction of reactive oxygen species to an unsaturated fatty acid moiety in phospholipids as a component of a cell membrane. As pathology, arteriosclerosis is widely known, which is caused by transforming macrophages that take up LDL having an oxidized lipid moiety into foam cells.
As an aging phenomenon that may be caused by reactive oxygen species/radicals, wrinkles, cataract, arthritis, and dementia are known.
Electrolytically reduced water containing hydrogen molecules has a negative oxidation-reduction potential, and is known to have an ability of scavenging the reactive oxygen species causing aging and diseases in the body, that is, antioxidation action. For health maintenance, drinking of electrolytically reduced water increases.
Further, a polyphenol contained in coffee has an ability of scavenging the reactive oxygen species, and there is a report in which coffee itself is effective in health maintenance.
For health maintenance, coffee obtained by extraction using electrolytically reduced water is drunk.
A conventional extraction method of coffee using electrolytically reduced water will be described with reference of FIG. 10. Basically, tap water 11 is supplied to an electrolytic cell. Cathode electrolytic water exiting from a cathode chamber 4 is heated by a heater (container) 2. A raw material for coffee or the like is subjected to extraction through a filter 7, and the produced extract is received by an extract receiver 8. As a method of effectively producing the extract from the raw material for coffee, an extraction method of coffee by supplying high-purity water obtained by purification of tap water as a source water with a reverse osmosis membrane device 1 to an electrolytic cell, as shown in FIG. 11, is known.